It is known that about 30% of total cataract surgery patients suffer from after-cataract (posterior capsular opacity), that is, a disease in which the remaining lens epithelial cells grow up and enter into the posterior capsule with an irregular array and the eye lens becomes cloudy.
Such after-cataract occurs in every age group, and particularly, it is being reported that the attack rate in the younger age groups is higher by 2 times that in the olderly.
More specifically, as illustrated in FIGS. 1 and 2, the lens epithelial cells proliferate continuously proliferate when they are exposed to the external environment after the cataract operation.
Accordingly, as the lens epithelial cells migrate into the posterior lens capsule, the relatively vacant space and subsequent cell transformation and proliferation occur, the light transparency and eyesight deteriorate, and the after-cataract occurs when the lens epithelial cells gathered in the posterior capsule completely deform.
Until now, the laser (with a Nd-YAG laser) surgery has been known as the only method for treating the after-cataract, but there has been a problem that eyesight becomes narrow after the laser surgery.
Therefore, it is more effective method to treat the after-cataract preemptively, but, up to now, only a method of providing a physical change to the support for the artificial lens used in the cataract surgery and the method of using a capsular tension ring have been provided as the methods of inhibiting the after-cataract.
Korean Pat. No. 0490286 discloses an eye drops composition for treating retinal damage which can treat retinal ischemia due to glaucoma, retinal damage due to diabetic retinopathy, degeneration of the retinal nerve due to uveitis, and so on by using sulfasalazine or a water-soluble salt thereof as the active component.
Korean Pat. No. 0490286 also discloses the pharmaceutical composition which can prevent and treat cerebral nerve diseases such as Parkinson's disease, Huntington's disease, Alzheimer's disease, and the like by using sulfasalazine as the active component.
However, it has been impossible to prevent or treat the after-cataract effectively even by these methods, and there has been no known method for preventing or treating the after-cataract by inhibiting the proliferation and migration of the cataract lens epithelial cells.